There is disclosed a pharmaceutical composition and method for treating sepsis, including septic shock and ARDS (acute respiratory distress syndrome), comprising administering an effective amount of a HMG1 antagonist. There is further disclosed a diagnostic method for monitoring the severity or potential lethality of sepsis or septic shock, comprising measuring the serum concentration of HMG1 in a patient exhibiting or at risk or exhibit sepsis or septic shock symptoms. Lastly, there is disclosed a pharmaceutical composition and method for effecting weight loss or treating obesity, comprising administering an effective amount of HMG1 or a therapeutically active HMG1 fragment.

SUMMARY OF THE INVENTION

The present invention provides a pharmaceutical composition for treating conditions (diseases) mediated by the inflammatory cytokine cascade, comprising an effective amount of an antagonist or inhibitor of HMG1. Preferably, the HMG1 antagonist is selected from the group consisting of antibodies that bind to an HMG1 protein, HMG1 gene antisense sequences and HMG1 receptor antagonists. The present invention provides a method for treating a condition mediated by the inflammatory cytokine cascade, comprising administering an effective amount of an HMG1 antagonist. In another embodiment, the inventive method further comprises administering a second agent in combination with the HMG1 antagonist, wherein the second agent is an antagonist of an early sepsis mediator, such as TNF, IL-1.alpha., IL-1.beta., MIF or IL-6. Most preferably, the second agent is an antibody to TNF or an IL-1 receptor antagonist (IL-1ra).

The present invention further provides a diagnostic and prognostic method for monitoring the seventy and predicting the likely clinical course of sepsis and related conditions for a patient exhibiting shock-like symptoms or at risk to exhibit symptoms associated with conditions mediated by the inflammatory cascade. The inventive diagnostic and prognostic method comprises measuring the concentration of HMG1 in a sample, preferably a serum sample, and comparing that concentration to a standard for HMG1 representative of a normal concentration range of HMG1 in a like sample, whereby higher levels of HMG1 are indicative of poor prognosis or the likelihood of toxic reactions. The diagnostic method may also be applied to other tissue or fluid compartments such as cerebrospinal fluid or urine. Lastly, the present invention provides a pharmaceutical composition and method for effecting weight loss or treating obesity, comprising administering an effective amount of HMG1 or a therapeutically active fragment thereof.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is based upon the discovery and isolation of a highly inducible 30 kDa protein that is released by, and accumulates in media conditioned by, cultured murine macrophage-like cells (RAW 264.7) following stimulation with LPS, TNF, or IL-1. A partial amino acid sequence of this isolated polypeptide was identical to the sequence of the HMG1 protein, also known as amphoterin, a protein not before linked to the pathogenesis of any disease. This information was used to clone a cDNA encoding HMG1, which sequence was expressed to provide recombinant protein, which protein was used to generate specific anti-HMG1 antibodies.

Therapeutic and diagnostic efficacy was determined in a series of predictive in vitro and in vivo experiments. The experiments are detailed in the Examples section. For example, following administration of endotoxin (LD.sub.100) to mice, serum HMG1 levels increased later (at 16 h) than well-known "early" mediators of sepsis (such as TNF and IL-1) and plateau levels of HMG1 were maintained for 16 to 32 hours. Patients with lethal sepsis had high serum HMG1 levels, which were not detected in normal healthy volunteers. Moreover, acute experimental administration of rHMG1 to test animals, whether alone or in combination with sub-lethal amounts of LPS, caused marked pathological responses and even death. More distributed dosing schedules of lower amounts of rHMG1 led to significant weight loss in treated animals. These results give evidence that HMG1 is a mediator of endotoxemia and particularly a late mediator, as opposed to known "early" mediators such as TNF and IL-1. These data further show the importance of serum HGM1 as a marker for the severity or potential lethality of sepsis and related conditions.

In addition, treatment with anti-HMG1 antibodies provided full protection from LD.sub.100 doses of LPS in mice. HMG1 is inducible by TNF and IL-1.beta., and dose-dependently stimulates TNF release from huPBMCs. TNF is a marker of macrophage activation, so it is likely (without limitation as to implied mechanisms or being bound by theory) that HMG1 promotes downstream re-activation of cytokine cascades which, in turn, mediates late pathogenesis and lethality in sepsis and related conditions involving activation of pro-inflammatory cytokine responses. Thus, HMG1 likely occupies a central role in mediating the inflammatory response to infection and injury, and antagonists of HMG1 will be of therapeutic benefit in sepsis and related conditions of inflammatory cascade activation. The appearance of HMG1 in the inflammatory cytokine cascade is suitable to propagate later phases of the host response and contribute to toxicity and lethality. The predictive data provided herein support the therapeutic efficacy of HMG1 antagonists and provide evidence in support of the aforementioned theory regarding mechanism of action. The in vivo treatment data showed the efficacy of HMG1 antagonists in general, and anti-HMG1 antibodies in particular, for treating conditions mediated by the inflammatory cytokine cascade in general and particularly sepsis conditions, including, for example, septic shock, sepsis syndrome or other "sepsis-like" conditions mediated by inflammatory cytokines. Further, the independent pathogenicity and toxicity/lethality of HMG1 shows that HMG1 antagonists are particularly effective when co-administered with antagonists of "early" inflammatory mediators such as TNF, MIF, IL-1 and IL-6.

In summary, HMG1 is a cytokine mediator of inflammatory reactions because: 1) HMG1 is released from macrophages and pituicytes following stimulation with bacterial toxins or with pro-inflammatory cytokines (TNF or IL-1.beta.), 2) HMG1 accumulates in serum of animals exposed to LPS and in patients with sepsis; and 3) HMG1-specific antibodies protect against mortality in a predictive lethal endotoxemia animal model of clinical sepsis and related conditions.

Pharmaceutical Composition and Method of Administration

The inventive pharmaceutical composition or inventive pharmaceutical combination can be administered to a patient either by itself (complex or combination) or in pharmaceutical compositions where it is mixed with suitable carriers and excipients. The inventive pharmaceutical composition or inventive pharmaceutical combination can be administered parenterally, such as by intravenous injection or infusion, intraperitoneal injection, subcutaneous injection, or intramuscular injection. The inventive pharmaceutical composition or inventive pharmaceutical combination can be administered orally or rectally through appropriate formulation with carriers and excipients to form tablets, pills, capsules, liquids, gels, syrups, slurries, suspensions and the like. The inventive pharmaceutical composition or inventive pharmaceutical combination can be administered topically, such as by skin patch, to achieve consistent systemic levels of active agent. The inventive pharmaceutical composition or inventive pharmaceutical combination can be formulated into topical creams, skin or mucosal patches, liquids or gels suitable for topical application to skin or mucosal membrane surfaces. The inventive pharmaceutical composition or inventive pharmaceutical combination can be administered by inhaler to the respiratory tract for local or systemic treatment.

The dosage of the inventive pharmaceutical composition or inventive pharmaceutical combination of the present invention can be determined by those skilled in the art from this disclosure. The pharmaceutical composition or inventive pharmaceutical combination will contain an effective dosage (depending upon the route of administration and pharmacokinetics of the active agent) of the inventive pharmaceutical composition or inventive pharmaceutical combination and suitable pharmaceutical carriers and excipients, which are suitable for the particular route of administration of the formulation (i.e., oral, parenteral, topical or by inhalation). The active agent is mixed into the pharmaceutical formulation by means of mixing, dissolving, granulating, dragee-making, emulsifying, encapsulating, entrapping or lyophilizing processes. The pharmaceutical formulations for parenteral administration include aqueous solutions of the active agent or combination in water-soluble form. Additionally, suspensions of the active agent may be prepared as oily injection suspensions. Suitable lipophilic solvents or vehicles include fatty oils such as sesame oil, or synthetic fatty acid esters, such as ethyl oleate or triglycerides, or liposomes. Aqueous injection suspensions may contain substances which increase the viscosity of the suspension, such as sodium carboxymethyl cellulose, sorbitol, or dextran. The suspension may optionally contain stabilizers or agents to increase the solubility of the active agent or combination to allow for more concentrated solutions.

Pharmaceutical formulations for oral administration can be obtained by combining the active agent with solid excipients, such as sugars (e.g., lactose, sucrose, mannitol or sorbitol), cellulose preparations (e.g., starch, methyl cellulose, hydroxypropylmethyl cellulose, and sodium carboxymethyl cellulose), gelaten, gums, or polyvinylpyrrolidone. In addition, a disintegrating agent may be added, and a stabilizer may be added.

Antisense Oligomers

The present invention provides antisense oligomers having a sequence effective to inhibit or block the expression of the HMG1 gene or mRNA sequence. Anti sense technology, which uses specific-oligonucleotides to inhibit expression of target gene products, is developing as a therapeutic modality for human disease. Several selection criteria are available to contribute to the optimization of antisense oligonucleotide antagonists. For example, it is advisable to choose sequences with 50% or more GC content. Preferred sequences span the AUG initiation codon of the target protein, but sites in the coding region and 5' UTR may perform equally well. Such sequences are generally about 18 30 nucleotides long and chosen to overlap the ATG initiation codon from the HMG1 cDNA sequence to inhibit protein expression. Longer oligomers are often found to inhibit the target to a greater extent, indicating that a preferred length is about 25 mer for the first oligonucleotides chosen as antisense reagents. Typically, three oligonucleotide sequences are chosen with regard to these criteria, and compared for antagonist activity to control oligonucleotide sequences, such as "reverse" oligonucleotides or those in which about every fourth base of the antisense sequence is randomized. Therefore, a preferred sequence for making antisense oligomer sequences to HMG1 is a 25 mer sequence chosen to overlap the ATG initiation codon (underlined) from the HMG1 cDNA sequence (see Original Patent).

The antibodies disclosed herein may be polyclonal or monoclonal; may be from any of a number of human, non-human eukaryotic, cellular, fungal or bacterial sources; may be encoded by genomic or vector-borne coding sequences; and may be elicited against native or recombinant HMG1 or fragments thereof with or without the use of adjuvants, all according to a variety of methods and procedures well-known in the art for generating and producing antibodies. Generally, neutralizing antibodies against HMG1 (i.e., those that inhibit biological activities of HMG1 particularly with regard to its pro-inflammatory cytokine-like role) are preferred for therapeutic applications while non-neutralizing antibodies may be as suitable for diagnostic applications. Examples of such useful antibodies include but are not limited to polyclonal, monoclonal, chimeric, single-chain, and various human or humanized types of antibodies, as well as various fragments thereof such as Fab fragments and fragments produced from specialized expression systems.
 

Claim 1 of 19 Claims

1. A method for treating a cardiovascular condition characterized by activation of the inflammatory cytokine cascade, comprising administering an effective amount of an antibody that specifically binds an HMG1 protein or an antigenic fragment thereof, wherein said antibody inhibits HMG1-mediated activation of the inflammatory cytokine cascade.

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